AlTNTVEltSART ADDRESS Ot' THE PRESIDENT. XXvii 



gnoWii by the papers which we were fortunate enough to obtain 

 from his perhaps too fastidious hands *. 



GEOLOGY, spreading with the growing intercourse of nations, is 

 constantly enlarging its field of observation, and gathering its charac- 

 teristic facts into laws of phsenomena. From time to time, as oppor- 

 tunities arise for successful research, or as some stand-point for the 

 interpretation of facts is fixed by chemistry, or mechanical philosophy, 

 or comparative physiology, the progress of our researches is more 

 marked in one direction than another. At one time, followiiig the 

 guidance of mathematical reasoning, we try to arrive at trustworthy 

 results regarding the internal constitution of the globe ; anon, with 

 surer aim, we bring into strong relief the long succession of mineral 

 deposits and the changes which they have experienced by the in- 

 cessant energies of nature operating through immensity of time ; and 

 we coordinate this succession and these changes with the series of 

 ancient organic life and the physical condition of the globe. 



After Seventy years of labour, the series of British strata— than 

 which none is more complete — has become known in its true 

 general sequence and in its principal local variations. Thfe large 

 tracts of primary strata in Wales, which eluded the strong grasp of 

 Sniith, have been probed to their thinly fossiliferous base by Sedg- 

 wick and Murchisou, and the Geological Surveyors treading in theif 

 steps; strata of equal antiquity in Ireland have jdelded a Small 

 suite of organic remains to the diligent followers of Griffith ; and 

 the latest work of Murchison, completing this toilsome labour, is 

 the tracing in Scotland of metamorphic rocks iU a 2onfe' bfelOw 

 MddUrea arid the oldest fossils of iSTorth America. If in this lotig 

 research we have not certainly reached an Azoic condition of the 

 globe, we have rendered it probable that such a coridition did oncc 

 obtain, because the sum of the- series of life, whether taken nume- 

 rically, or by physiological valuation of the several terms, diminished 

 as we go do^vnwards, by such a gradation as to point finally to zero, 

 fooln this point upwards, in the whole series of British strata,- 

 there is hardly one stratum whose place is doubtful, one place of 

 which the subjacent rock is quite unknown. There are few dis- 

 tricts and few strata whose fossils are without record ; few fossils 

 whose distribution in space and in time is not to some extent ascer- 

 tained. In this vast research the Geological Society has laboured 

 for more than half a century with well-rewarded patience, yet stni 

 has before it a mighty and pleasing labour, in fields opening Over 

 freshly to view. Every tract may be again surveyed with advan- 

 tage, every rock be re-examined for testing some law and confirm- 

 ing some truth. 



Exulting as we must do in the brilliant achievements of the Geo- 

 logical Survey, and pointing to the beautiful maps which already 



-^ " Oil Magnesian Breccia," Geol. Trans, ser. 1. vol. iv. p. 205. 

 " Oil some beds of Shell-marl in Scotland," Geo! Trans, ser. 1. vol. iv. p. 305. 

 " On Volcanic Chromate of Iron," Q-eol Trans, ser. 1. vol. v. p. 616. 

 " On the Bagshot Sand," G-eol. Trans, ser. 2. vol. i. p. 48. 

 •' On a bed of Septaria in Plastic Clay," Quart. Journ. Geol. Soc. vol. i. p. 172. 



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